Immunotherapeutic effects of tumor-specific transplantation antigens released by 1-butanol.

Active immunotherapy with materials extracted from a murine methylcholanthrene-induced sarcoma using single phase solutions of 2.5% 1-butanol evoked host resistance against supralethal burdens of neoplastic cells deposited subcutaneously or delivered hematogenously. After curative resection of progressing 1 cm tumors, postsurgical immunity against subsequent subcutaneous neoplastic challenges was potentiated by weekly injections of crude butanol extracts. In a conventional therapy model, hosts bearing progressing 4 mm subcutaneous tumors displayed neoplastic regression following chemoimmunotherapy with cyclosphosphamide and tumor extracts. Therapeutic effects were demonstrated not only against subcutaneous neoplasms, but also against hematogenously disseminated pulmonary and extrapulmonary metastases introduced by intravenous inoculation of sarcoma cells. These findings suggest that tumor extracts may afford potent therapeutic adjuvants for patients bearing a small body tumor burden but at high risk of disease recurrence.